Maintenance Flashcards
percent of total requirement used for maintenance for mature idle, lactating, and nursing foal
mature idle: 100%
lactating: 37%
nursing foal: 23%
T/F when DE is met other nutrient requirements are generally also met
TRUE
factors influencing maintenance energy requirement
body weight
digestive efficiency
activity level and temperament
environment
what type of horses have very high digestive efficiency? which have low?
high: babies, ones with high energy needs
low: old horses
why is weight tape not very effective
it was tested on the average sized quarter horse so that is the only type of horse it will be accurate on
why do small animals have higher metabolic rate
they have more surface area compared to body mass which makes them work harder to maintain body temp leading to greater oxygen consumption
T/F the curve of an absolute body weight graph is exponential, but metabolic body weight is linear
TRUE
T/F when comparing animals based on metabolic body size, energy needed for basal metabolism is similar
TRUE
equation for metabolic energy requirements
72 x BW^0.75
T/F there is a significant difference in DEm between low, average, and high energy needs
FALSE
what 2 categories is metabolizable energy used for
net energy
heat energy
what makes up net energy
tissue action
lactation
maintenance
what makes up heat energy
digestion/absorption
product formation
waste excretion
thermoregulation
what is DE of feeds affected by
gross energy of feed
digestibility of energy componants
what type of feeds do DE equations work for
individual feeds but not mixed formulas
components of 1989 NRC
-assumed diet composition for each class
-3 adjustment factors for differences in CP
-expressed CP requirements relative to DE intake
components of 2007 NRC
-data from different classes of horses
-expressed CP requirements relative to BW
why was the 2007 NRC better than the 1989
it takes into account horses at either end of the spectrum rather than just the average
how was the lysine requirement decided for sedentary horses
combining results from 7 studies that reported diet composition, intake, and N retention to estimate lysine
two types of analysis and what they estimated for lysine requirement
linear regression: minimum requirement
broken-line analysis: optimum requirement
T/F horses at maintenance should be fine on 100% forage
TRUE
expected feed consumption: total intake, forage, grain
total: 1.5-2% BW
forage: 1.5-2% BW
grain: 0-.5% BW
if hay/pasture is poor quality what may be needed in the diet
-ration balancing pellet
-oats
-fortified grain mix
why might heat decrease energy requirements
they are moving less
